private void GroupDetailView_DataContextChanged(object sender, DependencyPropertyChangedEventArgs e)
 {
     var model = DataContext as GroupViewModel;
     if (model != null) {
         _userListViewModel = new UserListViewModel(model.GetGroupUsers());
         _usersListView.DataContext = _userListViewModel;
     }
 }
 public DeleteUserCommand(UserListViewModel usersListViewModel)
 {
     _usersListViewModel = usersListViewModel;
 }
 public UsersDemoPage()
 {
     InitializeComponent();
     _userListViewModel = new UserListViewModel(FakeDataService.GetUsers());
     DataContext = _userListViewModel;
 }